Spring structure for seat cushions



June 11, 1 929. v A, EGGL. 1.716.518 I SPRING S'I RUCTURE FOR S EA'IfCUS HIONS Filed D60. 26, 1924 Patented June 11, 1929.

UNITED STATES Pa'rrirrr LOFFICE.

ADOLF EGG-LI, OF COLOGNE, GERMANY, ASSIGNOR TO E. W. SGHLAPPRIT ZI, OFMINNE- APOLIS, MINNESOTA.

SPRING STRUCTURE FOR SEAT CUSHIONS.

This invention relates to spring structures for seat cushions andrelates particularly to cushion structures employing leaf springs.

The invention consists in the structural features and arrangement ofparts hereinafter fully described.

In the drawings Figure 1 is a plan view-of the improved springstructure;

Figure'2 is a side view of the same;

Figure 3 is an end view;

Figure 4 is an enlarged view of a clip connecting two transverse tiemembers;

Figure 5 is a detail section on line 5.-5 of Figure 4.

In these views the reference character A designates a bottom borderframe comprised -braces A form a further reinforcement.

Preferably the rear bar A extends substantially the full length of thespring structure and is secured by clips A to the ends of the borderframe A. The end portions-of the bottom frame are respectivelyreinforced by braces A parallel to the braces A and extending from therear bar A to'the front member of thebottom frame,-being secured to thelatter by clips A The braces A are connected also to the ends of theframe A by short links A The top frame comprises simply a border memberB formed preferably of a resilient metal rod similar to that used in thebottom frame and corresponding in contour to the latter. The member B,-however, preferably employs no rear connecting portion between its ends,this beingbest seen in Figure 1. For resiliently mounting the top frameupon the lower one there is employed a plurality of leaf springs C, eachof an approximate semi-circular shape, said springs being arranged,preferably in opposed pairs, riveted or otherwise secured to the bars Aof the bottom frame, the ends of the opposed springs being convergent.The upper ends of each pair of opposed springs are connected A by a pairof tie members D formed of spring metal, the same being preferablyriveted to the springs C. Said tie members are extended forwardly beyondtheir points of connection with the front row of springs O, as indicatedat D, said portions D being terminally secured by clips D to the frontportion of the top frame. B. Thus the extensions of said tie membersconstitute a primary means for supporting the top frame upon thesprings. A secondary means for that purpose is formed by a pair of linksE which extend from the end ties D to the end portions of the top frame.

The end pairs of leaf springs C are opposed in a more closely adjacentrelation than the intervening springs owing to the reduction of spaceresulting from the rounded corners of the frames A and B. F is areinforcing strap formed of spring metal and connecting the tie membersD substantially along the longitudinal center line of the top frame.Said strap, as shown, is riveted at F to one tie member of each pair andis connected to the other tie member'by a sheet metal clip I providingfor a slight sliding movement between said strap and the ties. Eachofthe leaf springs C is provided with a reinforcement which takes effectunder predetermined conditions of severe stress. Thus an arcuate leafspring G is interiorly secured to each spring at substantially a midheight, preferably by a rivet G. The curvature of the re inforcingsprings G is of lesser radius than that of the main springs so that thelatter come into reinforcing engagement with the former only underconditions of considerable distortion, as shown in Figure 5.

Considering the structure now more fully with respect to the functionsof its various parts it will be readily understood that the top borderfr'ame B coacts with the tie members D to support the top upholstery(not shown) of a cushion. Under load the tie members D and likewise thelongitudinal reinforcing strapF will yield downwardly, stressing theleaf springs C. If the weight resting upon the structure is unusuallysevere the springs the structure is under stress,

ward each main springs C will engage the auxiliary G and be reinforcedthereby. The clip connections D between the tie members D and the topframe B are free to turn upon said frame when the tie members aredepressed under load.

The resilient nature of the rod B forming the top frame permits the endportions thereof to function as springs tending to maintain thelongitudinal strap member F normally taut and in the planeof said frame.When however, all or any portion of said strap member may be downwardlydeflected, this being permitted by a yielding of the ends of the topframe toother. When the structure is relieved of load the end portionsof the top spring will return to their maximum spaced relation,straightening said strap.

The sliding connections between the strap F and the tie members Dsecured where the links E are employed to establish such connections,permit such limited relative transverse movement of said strap and tiesas may be required by conditions of stress,

It is to be observed that both the top and bottom frames have a greaterextent from front to back and alsofrom end to end than the springs Cwhich is to be so that'the fabric coverin mounted upon the describestructure will be engaged solely with said top and bottom frame andnotsub]ected to wear and'deterioration by contact with the springs.

. adapted for What I claim as my invention is 1. A top frame for aspring cushion structure comprising a rod extending along the front andends of said structure having all portions spaced from the lower frameof said structure, said frame being open at its rear, the rear extreties of the ends of Said frame being curved toward each other.

2. A spring structure for cushion seats comrising top and bottom frames,the former liaving resilient end portions inte ral with thefrontportion, springs interme iate said frames, and a connection betweensaid end portions normally maintained thereby substantially in the planeof the top frame and deflection under load through stressing of said endportions toward each other. 1

3. A -spring structure for cushion seats comprising top and bottomframes, the forthrough stressing of said end portions toward each other.

4. A spring structure for seat cushions comprising top and bottomframes, the former having resilient end portions integral with the frontportion, leaf sprlngs arranged 1n opposed pairs and mounting the topframe on the bottom frame, a series of substantially comprising a bottomframe, and a top frame formed by a rod comprising front and end portionsonly, said end porti ns being resilient and free at their rearextremities, springs mounting saidtop frame on the bottom frame and atie connection between the end portions of the top frame adapted fordownward deflection under stress through springing of said portionstoward each other and normally held substantially in the plane of thetop frame by said portions.

6. A spring structure for seat cushions comprising top and bottomframes, one of which has resilient end portions integral with 1 thefront ortion thereof, springs intermedi ate said rames, and a connectionbetween said end portions normally maintained thereby substantially inthe plane thereof.

7. isprmg structure for' cushion seats comprislng a bottom frame havinga continuous red as its peripheral portion, and a top frame formedbyarod comprising front and end portions only, said endportions beingresilient and free at their rear extremities,

springs mounting said top frame on the bot-- tom frame, and a tieconnection between the end portions of the topframe adapted for-adownward deflection under stress through springing of said portionstoward each other I and normally held substantially in the plane of thetop frame by said portions.

8.. A spring structure. for cushion seats I.

comprising a pair of s aced frames, each of.

said frames having an integral rod as its peripheral member, theperipheral member of the lower frame-providing a complete enclosure, theperiphera member of the upper frame conforming substantially to thecontour of the lower frame, but having no rear portion, the end portionsof said upper peripheral member being resilient, springs mou nting' saidtop frame on the bottom frame, and a tie connection between the endportions of the top frame adapted for down ward deflection under stressthrough spring-' ing of said portions toward each other and normally h dsubstantially in the plane of the top frame by said portions.

9. A spring structu're'for cushion seats comprising top and bottomframes, the former. having resilient end portions integral with thefront sections, leaf springs arranged and transverse members extendedbetween in opposed pairs and mounting the top frame and connected attheir opposite ends to said on the bottom frame, tie members connectingouter tie members and said resilient end mem- 10 the paired leaf springat the top thereof and hers. 5 extended to engage and support the top Intestimony whereof I afiix my signature.

frame, a transversely extending member con- 4 nected at its ends to theouter tie members, ADOLF EGGLI.

